Steam injector



Sept. 3, 1929. l.. FRn-:DMANN 1,726,552

' STEAM INJEcToR Filed Dec. 5, 1924 llql- ATYORN EYS Patented Sept. 3, 1929.

UNITED STATES.

`PATENT OFFICE.

STEAM INJECTOR.

Application filed December 1924, Serial No. 754,200, and in Austria March 26, 1924.

My invention relates to steam injectors of the type commonly used for supplymg feed water to boilers and particularly locomotive boilers. This invention has for its 5' principal object to provide a simple andef ficient construction whereby the valve controlling the admission of the feed water to the injector is caused to be opened automatically whenever an amount of steam is admitted which is sufficient for the normal operation of thc injector, but said feed water valve will remain closed when only a small amount of steam is admitted, for instance such as will result from leakage at the steam admission valve. With the present improvement, therefore, no water will be fed to the injector if the amount of steam is below normal requirements for the operation of the injector, and the waste of water otherwise 2o occurring under such circumstances will be avoided.

A. satisfactory and preferred embodiment of this invention is illustrated bythe accompanying drawings, in f which Fig. 1 is a longitudinal vertical section through such a steam injector, and Fig. 2 is a partial cross section on the line 2-2 of Fig. 1.

At 1 I have indicated the main or innerl nozzle receiving steam from a conduit 1, This inner nozzle is surrounded by an outer nozzle 2 co-axial therewith and receiving steam through a conduit 2B. The mixing nozzle 3 is located in advance of the outer nozzle 2 and surrounds the tip ofV the inner nozzle 1. The pressure nozzle. 4 is arranged in advance of the mixing nozzle, the latter being surrounded by a chamber `5, inthe rear of the pressure chamber 6. Water reaches the wide end of the mixing nozzle 3 from a chamber 7 which has a valve-controlled con? nection with the water supply at 8. Any excess water is allowed to escape from the chamber 5 through an automatically operating valve 9.

An important feature of the present invention resides in the manner of actuating the valve which controls the connection from the feed water inlet 8 to the chamber 7. This valve 12 is spring-pressed and opens toward the inlet 8. Said valve is adapted to be engaged and opened,underconditions explained hereinafter, by the stem 11 of an actuating member 10, movable in the same direction as the valve and located within a casing 15 which it divides into two compartments 14 and 14a respectively.v Any suitable construction may be employed for the proper guiding of the valve-actuating member; for instance as indicated in Fig. 2 the said member may have a cross shaped guidemember 1()a in sliding engagement with the walls of the compartment 14. The two compartments 14 and 14il are in permanent communication with each other, in any suitable manner. The actuating member 10 therefore does not absolutely prevent` the passage of steam from the compartment 14 to the compartment 14, asa solid piston would do. In the example illustrated permanent communication between the two compartments.` 14 and 14 is established by making the'actuating member 10 of suiiciently smaller ydiameter than the inside of casing 15, to leave a clearance all around the periphery of said member. The compartment 14 communicates.l permanently with one of the steam conduits 1, 2.a, for instance the latter, by means of a .channel 13. Thecompartment 14a communicates normally with the water chamber 7 by a channel 16, through which the stem 11 vof the actuating member llextends witha suicient clearance toprovide an ample passage for any small lamount of steam flowing from the conduit 2a through the channel 13 and through the compartmentsl 14, 14a past `the actuating member 10, which is interposed between the channels 13, 16.

At its inner end, the channel 16 is formed with a valve seat b, adapted to be engaged by a corresponding valve portion aon the `actuating member 10.

The conduits 1a, 2a receive steam from any suitable source.` In the example illustrated, both conduits receive steam `from the same source, such steam being live steam either di'- rectly from the boiler or through some intermediate connection.y Steam enters an admission chamber 18 through an inlet 19, the outlet of said chamber being normally closed by the steam pressure acting against a valve 20. This valve may be opened in any suitable manner, for instance manually by means of a lever 21' operatively connected with the valve stem 22. As soon as the valve 20 is opened, steam will pass to the conduit 2a, in suliicient volume to cause the amount which is diverted from the inlet 8 to the chamber 7 and to they mixing nozzle 3, the injector' being thus started with the aid of the steam reaching the outer nozzle 2 from the conduit 2t.

Vith the valve 2O is connected so as to move in unison therewith, another valve 17,

normally closingthe inlet end of thest-eam conduit 1?.'

The relative arrangement of these two valves 20, 17 is such that the valve 17 will not openuntil the valve 20 has been lifted acertain distance from its seat, so that steam will be admitted first to the conduit 2a, to start the injector, and then to the conduit 1, both conduits then receiving steam orthe normal injector operation. Atl this time the actuating member 10 becomes seated on the seat b, thus closing the communication between compartment 14a andv chamber 7.

While the valves 20, 17 are closed, the actuating member 10is out of contact with its seat I). rvUnder these circumstances, should a small amount of steam pass into the compartment e 14 through the channel 13,**as may occur, for

instance, if there should be a leakage of steam past ,thevalve 20, such iow of steam will not be strong enough to move the actuating member 10, but will pass around the/edge of said member intothe compartment 14, and out of the latter through the channel 16 `into the water chamber 7. Thus, by preserving a permanent communication between the compartments .14, 14a, I prevent the actuating member 10 and valve 12 from being operated by a slow 'flow' of steam, and insure their being operated only when intended.v I thus avoid the loss of water that would resultif the valve 12 were to open even upon the admission of a small amount of steam to the compartment 14.'l Another advantage of employing an actuating member 10 of the character described, consists in avoiding or reducing the liabilityV of such member to stick in its guides, as compared withjan ordinary piston. The operation therefore .becomes more reliable.

` Various modifications may be made without departing from the nature of my invention as set forth in the appended claims.

I vclaim as my invention:

1. In an injector, a high pressure steam nozzle and a low pressure steam nozzle, individual steam conduits leading to said nozzles, a water-supply conduit, a valve controlling the last-mentioned conduit, -a casing located adjacent to said valve and having two channels, one in communication with said water conduit and the other in communication. with the conduit leadingto said low pressure nozzle, and an actuating member mounted movably in said casing, between said two channels and adapted to engage said valve to open the same when a suiicient amount of steam flows through the conduit for the low pressure nozzle and into said casing to establish the jet action of the injector, there being a permanent communication between the twochannels of the casing on opposite sides of said member, so that a moderate lamount of steam may pass from said steam conduit through the casing past said member without actuating the latter.

2. In an injector, a high pressure steam nozzle and a low pressure steam nozzle, a steam supply conduit having a pair of branches leading one to each of said nozzles,

a water supply conduit, a normally closed i;

`valve for controlling the admission of water through said water conduit, a casing adjacent to said water conduit, having a restricted opening in communication with the branch conduit leading to saidlow pressure nozzle and inparallel with said low pressure nozzle, said casing having a second opening leading to saidwater conduit and an actuating member movably mounted in said casing between saidy two openings and adapted to engage said valve to open the same when the amount of steam owing to said low pressure nozzle through the low'pressure steam branch is sufficient to establish the injector et, there being a clearance space between said actuating member and said casing so that'a moderate amount `of steam may pass from said steam conduit through the casing past said member without actuating the latter.

\ 3. In an injector, a high pressure steam nozzle and a. low pressure steam nozzle, a steam conduit communicating with said low pressure steam nozzle, a water supply conduit including a casing, a water control valve mountedinsaid casing, a by-pass leading v:from said steam conduit and communicting through said casing-with said water-supply conduit and a fluid pressure actuated member foropening said water control valve, said member being movably mounted in said casing inthe path of the steam flow through said by-pass, and there being a suiiicient clearance between said casing and member so ,that the latter will be actuated by said steam flow. to open said valvel only when enough steam is flowing to said low pressure steam nozzle to insure the establishment of the'inj ector jet.

4. In an injector, a high pressure steam nozzle and a low pressure steam nozzle, individual steam supply conduits leading to said nozzles, a water-supply conduit, a normally closed admission valve controlling said water supply conduit, a casing adjacent to said admission valve having a. fluid pressure actuated member movably mounted therein for opening said admission valve, the steam supply conduit for said low pressure nozzle having a pair of parallel branches,

llO

one communicating with said nozzle and one opening of the conduit leading to the low with said casing, said casing being provided pressure nozzle and casing will be effected be- With an opening communicating with said fore steam is admitted to the high pressure 10 Water supply conduit, and a pair of manually nozzle.

' operable Valve members for admitting steam In testimony whereof I have hereunto set to said steam supply conduits, said valve my hand. members being so interconnected that a full LOUIS FRIEDMANN. 

